Fuel Tank

Complete removal and replacement of the fuel tank assembly on a 2015-2020 Ford F-150 with 3.5L EcoBoost engine, including disconnection of fuel lines, electrical connections, and support straps.

Warnings

Tools required

Parts

• Fuel tank assembly × 1 — Use OEM specification
• Fuel tank straps (if corroded) × 2 — Use OEM specification
• Fuel line O-rings × 4 — Use OEM specification
• Fuel filler neck seal/gasket × 1 — Use OEM specification
• EVAP line quick-connect seals × 2 — Use OEM specification
• Fuel pump module gasket (if replacing pump) × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface in well-ventilated area away from all ignition sources, pilot lights, and sparks
2. Ensure fuel tank is as empty as possible (ideally less than 1/4 tank)
3. Disconnect negative battery cable and wait 10 minutes for system capacitors to discharge
4. Raise vehicle on lift or support securely on jack stands rated for vehicle weight
5. Remove spare tire and lower spare tire carrier completely out of work area
6. Place drain pan under fuel tank area
7. Have fire extinguisher immediately accessible before proceeding

Procedure

1. 1

   Relieve fuel system pressure
   Locate the fuel pump relay in the battery junction box (relay #27 in 2015-2017 models, verify in owner's manual). Remove the fuel pump relay. Attempt to start the engine and let it run until it stalls from fuel starvation. Attempt to start again to confirm system is depressurized. Turn ignition off and reinstall relay (do not reconnect battery yet).
   ⚠️Engine will run briefly and stall. This is normal. Do not attempt to restart more than twice or you may damage catalytic converters.
2. 2

   Disconnect fuel filler neck
   From rear driver's side area, locate the fuel filler neck connection to the tank. Use appropriate tool to loosen the filler neck hose clamp at the tank connection point. Disconnect the filler neck hose from tank inlet pipe. Disconnect EVAP vent line from filler neck assembly using quick-disconnect tool.
   ⚠Residual fuel will drain from filler neck. Have drain pan positioned to catch spillage.
   Torque spec

   Filler Neck Clamp4 Nm (3 lb-ft)
3. 3

   Disconnect electrical connections
   Locate the fuel pump module electrical connector on top of the fuel tank (accessible from underneath vehicle). Press the locking tab and disconnect the electrical connector. Disconnect any additional sensors including fuel level sensor if equipped with separate connector. On trucks with frame-mounted EVAP canister, disconnect canister electrical connector.
4. 4

   Disconnect fuel supply and return lines
   Identify the fuel supply line and return line at the front of the fuel tank. Using the appropriate spring lock coupling disconnect tool, compress the spring tabs and disconnect both fuel lines from the tank connections. Verify spring lock couplings are fully released before pulling lines. Cap or plug open lines immediately to prevent contamination.
   ⚠Residual fuel under pressure may spray when lines are disconnected. Have shop towels ready and wear eye protection.
5. 5

   Disconnect EVAP lines
   Locate EVAP vapor lines connecting to top of fuel tank (typically 2-3 lines depending on configuration). Use appropriate quick-disconnect tools to release EVAP line connections. Note routing and orientation of each line for reinstallation. Secure lines out of the way.
6. 6

   Position tank support
   Position transmission jack or dedicated fuel tank jack under center of fuel tank. Raise jack until it just contacts tank bottom with light pressure. Place wide wooden board or tank support adapter between jack and tank to distribute load evenly. Ensure tank is stable and balanced on jack before proceeding.
   ⚠️Tank must be properly supported before loosening straps. An unsupported or unbalanced tank can fall causing severe injury.
7. 7

   Remove heat shields if equipped
   If equipped with exhaust heat shields above fuel tank, remove mounting bolts and lower shields. Note position for reinstallation. Some models have multiple shield sections that must be removed to access tank straps.
   Torque spec

   Mounting Bolts31 Nm (23 lb-ft)
8. 8

   Remove fuel tank strap bolts
   Locate the two fuel tank support straps that wrap around tank and bolt to frame on each side. Support each strap with one hand while removing the strap mounting bolts with the other. On 2015-2020 F-150, remove the rear bolt from each strap first, then the front bolt. Allow straps to swing down but do not remove completely until tank is lowered.
   ⚠Straps are under tension and may swing down forcefully when bolts are removed. Control strap movement to prevent injury.
   Torque spec

   Tank Strap Bolts35 Nm (26 lb-ft)
9. 9

   Lower fuel tank partially
   Carefully lower transmission jack approximately 6-8 inches while monitoring all connections. Verify no electrical connectors or lines are still attached and preventing tank movement. If resistance is felt, stop and inspect for forgotten connections. Do not force tank downward.
10. 10

    Disconnect remaining hard lines and shields
    With tank partially lowered, access is now available to any remaining hard fuel lines or EVAP lines on top of tank. Disconnect any lines not accessible in previous steps. Remove tank straps completely if they did not release during lowering. On some configurations, a small protective shield may need removal from tank top.
11. 11

    Remove fuel tank from vehicle
    Continue lowering transmission jack slowly while guiding tank to ensure it clears frame rails and exhaust components. Tank may need to be angled slightly during removal. Once clear of vehicle, lower jack completely and carefully roll tank assembly to safe work area. If fuel remains in tank, use approved fuel transfer pump to drain into approved container.
    ⚠️Tank is awkward and heavy even when partially full. Get assistance if needed. Never allow tank to fall or drop onto jack or floor.
12. 12

    Install new or serviced fuel tank
    Position new or serviced fuel tank on transmission jack. If replacing fuel pump module, install now with new gasket and proper torque before installation. Raise tank into approximate position beneath vehicle. Install new O-rings on all fuel line connections - lubricate lightly with clean engine oil. Align tank to frame mounting points.
    ℹ️All fuel line O-rings must be replaced with new components. Reusing old O-rings will result in fuel leaks.
    Torque spec

    Fuel Line Fittings25 Nm (18 lb-ft)
13. 13

    Reconnect lines and electrical connections
    With tank raised to working height, reconnect hard fuel lines on top of tank ensuring spring lock couplings click fully into locked position. Pull on each line to verify engagement. Reconnect all EVAP lines and verify proper routing. Connect fuel pump electrical connector and any additional sensor connectors. Verify all connections are secure.
14. 14

    Install tank straps and secure tank
    Raise tank to final position aligning mounting points with frame. Position tank straps around tank. Install strap mounting bolts hand-tight first to verify alignment. Torque tank strap bolts to specification in crossing pattern (alternate front-to-rear on each side). Verify tank is centered and secure before removing jack support.
    Torque spec

    Tank Strap Bolts35 Nm (26 lb-ft)
15. 15

    Complete final connections
    Reinstall heat shields if equipped and torque mounting bolts to specification. Reconnect fuel filler neck hose to tank inlet and secure with clamp torqued to specification. Reconnect EVAP line to filler neck. Connect fuel supply and return lines at front of tank, ensuring spring lock couplings fully engage. Lower vehicle to access height and reconnect negative battery cable.
    Torque spec

    Filler Neck Clamp4 Nm (3 lb-ft)

    Mounting Bolts31 Nm (23 lb-ft)

Reassembly

1. Reinstall spare tire carrier and spare tire
2. Double-check all electrical connections are fully seated and locked
3. Verify all fuel line connections by pulling firmly on each line to confirm engagement
4. Ensure tank straps are torqued properly and tank does not move when pushed upward
5. Confirm all tools and equipment are removed from under vehicle

Verification

• With vehicle still raised, add 2-3 gallons of fresh fuel to tank and inspect all connections for leaks for 5 minutes
• Reconnect battery and turn ignition to ON position (do not start) and listen for fuel pump activation. Pump should run 2-3 seconds then stop
• Inspect all connection points again for fuel leakage while pump is running
• Start engine and allow to idle for 5 minutes, monitoring for fuel odors or visible leaks underneath vehicle
• With engine running, inspect tank area, all fuel lines, filler neck, and EVAP connections for any signs of leakage
• Turn engine off and perform final visual inspection of entire fuel system
• Road test vehicle and monitor fuel gauge operation and check engine light. Perform final leak inspection after test drive
• If any fuel odor is detected or leaks are found, immediately shut off engine and repair before operating vehicle

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